The secret of a restaurant chain's success could be the secrecy of their menus, according to...

The secret of a restaurant chain's success could be the secrecy of their menus, according to industry analysts. After In-N-Out Burger used the insider jargon to boost sales for years, other companies are warming up to the idea. Panera Bread (PNRA-0.3%) is in the game with its view that viral social media buzz will take of the marketing side for minimal cost. (PNRA secret menu)